|Martian in the Mirror|
Want to see a Martian? Look in the mirror.
New evidence has emerged which supports the long-debated theory that life on Earth may have started on Mars.
"It's only when molybdenum becomes highly oxidized that it is able to influence how early life formed. This form of molybdenum couldn't have been available on Earth at the time life first began, because three billion years ago the surface of the Earth had very little oxygen, but Mars did. It's yet another piece of evidence which makes it more likely life came to Earth on a Martian meteorite, rather than starting on this planet."
Professor Benner's research focuses on two paradoxes which make it difficult for scientists to understand how life could have started on Earth.
The first is dubbed by Professor Benner as the 'tar paradox'. All living things are made of organic matter, but if you add energy such as heat or light to organic molecules and leave them to themselves, they don't create life. Instead, they turn into something more like tar, oil or asphalt.
"Certain elements seem able to control the propensity of organic materials to turn into tar, particularly boron and molybdenum, so we believe that minerals containing both were fundamental to life first starting. Analysis of a Martian meteorite recently showed that there was boron on Mars; we now believe that the oxidized form of
molybdenum was there too."
The second paradox is that life would have struggled to start on the early Earth because it was likely to have been totally covered by water. Not only would this have prevented sufficient concentrations of boron forming – it's currently only found in very dry places like Death Valley – but water is corrosive to RNA, which scientists believe was the first genetic molecule to appear. Although there was water on Mars, it covered much smaller areas than on early Earth.
sources: European Association of Geochemistry; Professor Steven Benner
Marvin the Martian
NASA Mars Curiosity Rover Spacecraft
The Search for Life That Is Very, Very Different from Our Own
As a consequence of space exploration and the realization that life on other planets might be very different from what we are used to, scientists in recent decades have improbably discovered bizarre life forms here at home in places previously deemed uninhabitable.
This book provides a bestiary of weird creatures, both real and imagined, and describes the science behind their existence.